CA2550597C - Iron-based powder composition comprising a combination of binder-lubricants and preparation of the powder composition - Google Patents

Iron-based powder composition comprising a combination of binder-lubricants and preparation of the powder composition Download PDF

Info

Publication number
CA2550597C
CA2550597C CA2550597A CA2550597A CA2550597C CA 2550597 C CA2550597 C CA 2550597C CA 2550597 A CA2550597 A CA 2550597A CA 2550597 A CA2550597 A CA 2550597A CA 2550597 C CA2550597 C CA 2550597C
Authority
CA
Canada
Prior art keywords
iron
weight
polyethylene wax
powder
composition
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CA2550597A
Other languages
French (fr)
Other versions
CA2550597A1 (en
Inventor
Mats Larsson
Asa Ahlin
Maria Ramstedt
Hilmar Vidarsson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hoganas AB
Original Assignee
Hoganas AB
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hoganas AB filed Critical Hoganas AB
Publication of CA2550597A1 publication Critical patent/CA2550597A1/en
Application granted granted Critical
Publication of CA2550597C publication Critical patent/CA2550597C/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/10Metallic powder containing lubricating or binding agents; Metallic powder containing organic material
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/10Metallic powder containing lubricating or binding agents; Metallic powder containing organic material
    • B22F1/102Metallic powder coated with organic material
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/12Metallic powder containing non-metallic particles
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C33/00Making ferrous alloys
    • C22C33/02Making ferrous alloys by powder metallurgy
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2998/00Supplementary information concerning processes or compositions relating to powder metallurgy

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Powder Metallurgy (AREA)
  • Lubricants (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

The invention concerns an improved segregation-resistant and dust-resistant metallurgical composition for making compacted parts, comprising at least about 80 percent by weight of an iron or iron-based powder; at least one alloying powder; and (c) about 0.05 to about 2 percent by weight of a binding/lubricating combination of polyethylene wax and ethylene bis-stearamide, the polyethylene wax having a weight average molecular weight below about 1000 and a melting point below that of ethylene bisstearamide, and being present in amount between 10 and 90% by weight of the binding/lubricating combination.

Description

IRON-BASED POWDER COMPOSITION COMPRISING A COMBINATION OF
BINDER-LUBRICANTS AND PREPARATION OF THE. POWDER COMPOSITION.
FIELD OF THE INVENTION
The present invention relates to a new metal powder com-position for the powder metallurgical industry. Particu-larly the invention relates to an iron-based powder com-position which contains a binding composition which also provides lubrication during the compaction process used to form a part.

BACKGROUND OF THE INVENTION
In industry the use of metal products manufactured by compacting and sintering iron-based powder compositions is becoming increasingly widespread. The quality require-ments of these metal products are continuously raised, and as a consequence new powder compositions having im-proved properties are developed. One of the most impor-tant properties of the final, sintered products is the density and dimensional tolerances, which above all have to be consistent. Problems with size variations in the final product often originates from inhomogenities in the powder mixture to be compacted. These problems are espe-cially pronounced with powder mixtures including pulver-ulent components, which differ in size, density and shape, a reason why segregation occurs during the trans-port, storage and handling of the powder composition.
This segregation implies that the composition will be non-uniformly composed, which in turn means that parts made of the powder composition are differently composed and consequently have different properties. A further problem is that fine particles, particularly those of lower density such as graphite, cause dusting in the handling of the powder mixture.

The small particle size of additives also create problems with the flow properties of the powder, i.e. the capacity of the powder to behave as a free-flowing powder. An im-paired flow manifests itself in increased time for fill-ing dies with powder, which means lower productivity and an increased risk of variations in density in the com-pacted component, which may lead to unacceptable deforma-tions after sintering.

Attempts have been made at solving the problems described above by adding different binding agents and lubricants to the powder composition. The purpose of the binder is to bind firmly and effectively the small size particles of additives, such as alloying components, to the surface of the base metal particles and, consequently, reduce the problems of segregation and dusting. The purpose of the lubricant is to reduce the internal and external friction during compaction of the powder composition and also re-duce the ejection force, i.e. the force required to eject the finally compacted product from the die.

Various organic binding agents are disclosed in for exam-ple the US patent 4 483 905 (Engstrom) which teaches the use of a binding agent that is broadly described as being of "a sticky or fat character". The US patent 4 676 831 (Engstrom) discloses the use of certain tall oils as binding agents. Furthermore the US patent 4 834 800 (Semel) discloses the use of certain film-forming poly-meric resins that are insoluble or substantially insolu-ble in water as binding agents.

Other types of binding agents set forth in the patent literature are polyalkylene oxides having molecular weights of at least about 7000, which are disclosed in the US patent 5 298 055 (Semel). Combinations of dibasic organic acid and one or more additional components such as solid polyethers, liquid polyethers, and acrylic res-ins as binding agents are disclosed in the US patent 5 290 336. Binding agents that can be used with high tem-perature compaction lubricants are disclosed in the US
patent 5 368 630 (Luk).

Furthermore, the US patent US 5 480 469 (Storstrom) pro-vides a brief review of the use of binding agents in the powder metallurgy industry. The patent notes that it is important to have not only a powder composition that has the alloying powder adhered to the iron-based powder by way of the binding agent, but to also have a lubricant present to achieve adequate compressibility of the powder composition within the die and to decrease the forces re-quired to remove the part from the die.

Specifically, the US patent 5 480 469 teaches a method for binding additives in an iron-based powder metallurgi-cal mixture to the iron or iron-based powder particles by the use of a diamide wax binder. In order to achieve an effective binding between the iron or iron-based parti-cles and the additive particles the powder metallurgical mixture including the binder is mixed and heated to about 90-160 C during mixing and melting of the binder, and subsequently the mixture is cooled during mixing, until the binder has solidified. By this method the flow and apparent density is substantially improved and the prob-lem with dusting can be reduced or eliminated.

A property of a powder mix which is not specifically dis-cussed in the US patent 5 480 469 is the lubricating property. This property is of particular importance when components having high density and/or a complex shape are required. In connection with the production of such com-ponents it is essential that the lubricating properties of the used powder metallurgical mixture are good which in turn means that the energy needed in order to eject to component from the die, i.e. the ejection energy, should be low which is a pre-requisite for a satisfactory sur-face finish of the ejected component, i.e. a surface fin-ish without any scratches or other defects.

We have now developed a new iron or iron based composi-tion which is distinguished by low segregation and low dusting, good flow and high apparent density and which is also distinguished by good lubricating properties i.e.
properties which are all important for powders to be com-pacted and sintered to high quality products.
SUMMARY OF THE INVENTION
In brief the iron or iron-based composition according to the presnt invention includes at least about $O percent by weight of an iron or iron-based powder; at least one alloying powder in an amount up to about 20 percent by weight;
and about 0.05 to about 2 percent by weight of a combina-tion of polyethylene wax and ethylene bisstearaimide. The polyethylene wax should have a weight average molecular weight below about 1040 and a melting point below that of ethylene bis.st.earamide.. Furthermore, the amount of the polyethylene wax should vary between 10 and 9,04 by weight of the total weight of the binding/lubricating combina-tion of polyethylene wax and ethylene bisstearamide. In the powder composition used for compaction the polyethy-lease wax is present as a layer or coating on the iron or iron-based particles and binds the alloying element par-ticles and the ethylene bsstearamide particles to the iron or iron-based particles. It is preferred that the composition also includes a fatty acid and a flaw. agent..
The invention. also concerns a method of preparing the powder composition to be compacted.

4a According to another aspect of the present invention, there is provided an improved segregation-resistant and dust-resistant metallurgical composition for making compacted parts, comprising: (a) at least about 80 percent by weight of an iron or iron-based powder;
(b) at least one alloying powder; and (c) about 0.05 to about 2 percent by weight of a binding/lubricating combination of polyethylene wax and ethylene bis-stearamide, the polyethylene wax having a weight average molecular weight below about 1000 and a melting point below that of ethylene bis-stearamide, and being present in an amount between 10 and 90% by weight of the binding/lubricating combination, wherein the particles of the iron or iron-based powder are coated with a layer of the polyethylene wax binding particles of the alloying element(s) and particles of the ethylene bis-stearamide.

According to still another aspect of the present invention, there is provided method of preparing an improved segregation-resistant and dust-resistant metallurgical composition containing alloying powder bound to iron-based powder comprising the steps of mixing and heating an iron or iron-based powder, an alloying element powder, ethylene bis-stearamide and a pulverulent polyethylene wax and optionally a fatty acid to a temperature above the melting point of the polyethylene wax and below the melting point of the ethylene bis-stearamide cooling the obtained mixture to a temperature below the melting point of the polyethylene wax for a period of time sufficient to solidify the polyethylene wax and bind the particles of the alloying element to the iron-containing particles in order to form aggregate particles, and optionally mixing a pulverulent flow agent having a particle size below 200 nanometers, with the obtained mixture in an 4b amount between 0.005 to about 2% by weight of the composition.

DETAILED DESCRIPTION OF THE INVENTION

As used in the description and the appended claims, the expression "iron or iron-based powder"
encompasses powders prepared by atomization, preferably water atomization. Alternatively, the powder may be based on sponge iron. The powders may be essentially pure iron powders preferably such powders, which have high compressibility.
Generally, such powders have a low carbon content, such as below 0.04% by weight. Other examples of powder are 5 iron powders that have been pre-alloyed or partially.al-loyed:with other substances improving the strength, the hardening properties, the electromagnetic properties or other desirable properties of the end products. Examples of powders are e.g. Distaloy Al, AstaloyMMo and ,ASCTM
100.29, all of which are commercially available from Hbgazas AS, Sweden..

The particle size of the iron or iron-based particles normally have a maximum weight average particle size up l5 to about 500 microns; more preferably the particles will have a weight. average particle size in the range of about 25-150 microns, and most preferably 40-100 microns.
Examples of alloying elements are copper, molybdenuri, chromium, nickel, manganese:, phosphorus, carbon in the form of graphite, and tungsten, which are used either separately or'in combination. These additives are gener-ally powders having a smaller particle size than the base iron powder and most additives have a particle size smaller than about 20 }zm, The ' molecular weight of polyethylene wax has an impact on the powder properties and it has been found that a combi-nation of good flow, high apparent density and low ejec-.30 Lion energy may be obtained with a low molecular weight polyethylene which. in connection with the present inven-tion means .,a linear polyethylene having a weight Average, molecular weight below.1000, particularly below 800 and above 300 particularly above 400. In addition to the mo-lecular weight of the polyethyelene wax the ratio between., the ethylene bis stearamide and the polyethylene wax in-fluences these properties. Ethylene bis stearamide .is available as e.g. Acrawax or Licowax . Polyethylene wax is available from Allied Signal and Baker Petrolite.
According to the present invention and as is illustrated by the examples the relative amounts of polyethylene wax and ethylene bisstearamide are important. In the bind-ing/lubricating combination of polyethylene wax and eth-ylene bisstearamide it has thus been found that 10-90% by weight should be polyethylene wax. According to the pre-sently most preferred embodiment the amount of polyethy-lene wax should be present in 20-70% by weight of the binding/lubricating combination. If more than 90% by weight of polyethylene wax is used, the lubrication will be in most cases insufficient and if more than 90% by weight of ethylene bisstearamide is used, the binding will be insufficient. The total amount of bind-ing/lubricating combination in the composition is pref-erably between 0.5 and 1% by weight.

The improved segregation-resistant and dust-resistant metallurgical composition according to the invention can be defined as a composition containing at least about 80 percent by weight of iron-based powder; at least one al-loying powder; and about 0.05 to about 2 percent by weight of a partially melted and subsequently solidified binding/lubricating combination adhering the alloying powder particles to the iron or iron-based powder parti-cles.

Low molecular polyethylene waxes have been mentioned in connection with iron-based metal powders for the PM-in-dustry in e.g. the US patent 6 605 251 (Vidarsson) wherein it is disclosed that polyethylene waxes can be used as lubricants in warm or cold compaction of iron or iron based powders. When used in warm compaction the mix-ture including the polyethylene wax is heated to a tem-perature below the melting point of the polyethylene wax before compaction. The US patent 6 602 315 (Hendrickson) and the related US patent 6 280 683 (Hendrickson) dis-close the use of low molecular polyethylene wax in bonded mixtures. The bonding effect is achieved by the wax at an elevated temperature which is below the melting point of the wax. The illustrating examples which concern iron or iron-based powders indicate that none of the samples ex-hibited flow. Furthermore the US patents 6 533 836 (Uenosono)and 6 464 751 (Uenosono) disclose a free lubri-cant of low molecular polyethylene wax and etylenbis-stearamid in combination with a binder which comprises at least one member selected from the group consisting of stearic acid, oleamide, stearamide, a melted mixture of stearamide and ethylenbis(stearamide) and ethylen-bis(stearamide). The binder may also comprise zinc stearate and at least one member selected form the group consisting of oleic acid, spindle oil and turbine oil.
According to the present invention it is also preferred that the starting mix in addition to the iron or iron-based powder, the alloying powder and the polyethylene wax and the ethylene bisstearamide also includes a fatty acid, preferably a fatty acid having 10-22 C atoms. Exam-ples of such acids are oleic acid, stearic acid and palmitic acid. The amount of the fatty acid is normally 0.005-0.15, preferably 0.010-0.08 and most preferably 0.015-0.07% calculated on the total weight of the powder composition. Fatty acid contents below 0.005 make it dif-ficult to achieve an even distribution of the fatty acid.
If the content is higher than 0.15 there is a consider-able risk that the flow will deteriorate.

It is furthermore preferred that a flow agent of the type disclosed in the US patent 5 782 954 (Luk)is included in the composition after the bonding has been completed.
Preferably this flow agent is silicon oxide, most pref-erably silicon dioxide having an average particle size of below about 40, preferably from about 1-35 nanometers and it is used in an amount from about 0.005 to about 2, preferably 0.01-1 percent by weight, most preferably from 0.025 to 0.5 percent by weight of the total composition.
Other metals that can be used as flow agents in either its metal or metaloxide forms include aluminium, copper, iron, nickel, titanium, gold, silver, platinum, palla-dium, bismuth, cobalt, manganese, lead, tin, vanadium, yttrium, niobium, tungsten and zirconium with a particle size of less than 200 nm.

The process for preparing the new powder composition in-cludes the steps of mixing and heating a mix of an iron or iron-based pow-der, an alloying element powder, ethylene-bisstearamide and a pulverulent polyethyelene wax and optionally a fatty acid to a temperature above the melting point of the polyethylene wax, and below the melting point of EBS
-cooling the obtained mixture to a temperature below the melting point of the polyethyelene wax for a period of time sufficient to solidify the polyethyelene wax and bind the particles of the alloying element to the iron-containing particles in order to form aggregate parti-cles, and optionally, -mixing a pulverulent flow agent having a particle size below 200 nanometers, preferably below 40 nanometers, with the obtained mixture in an amount between 0.005 to about 2% by weight of the composition. The heating is suitably performed at a temperature between 70 and 150 C
for a period between 1 and 60 minutes.

The invention is further illustrated by the following non limiting examples, wherein the following ingredients and methods were used:
Iron powder-AHC 100.29 from Hoganas AB (Sweden) Graphite uf4 from Kropfmuhl Polyethylene wax 440, 500, 655, 750 and 1000 from Baker 'Petrolite (USA).
Ethylene bisstearamide (EBS) available as LicowaxTM from Clariant (Germany) The stearic acid is available from Faci (Italy) Aerosil is available from Degussa AG (Germany).

The flow was measured. according to according to ISO 4490.
The apparent density was measured. according to ISO 3923, The. Ejection Energy was evaluated. in an instrumented 125 tons hydraulic uniaxial laboratory press. Force and dis-placement are registered during ejsection of the compact i5 Ejection energy is calculated by integrating the force with respect to the displacement of the ejected part'.
Ejection energy is expressed as energy per envelope Sur-face area.

Dusting was measured by subjecting 5 grams of the sample to a flow of air of 1,7 .liter/m.inute_ , particle's less than 10 micr'Qns transported by the, air stream. were counted by a measuring instrument Dust Track Aerosol Monitor model 8520 . Dusting is expressed as mg/m. .
The part bonded graphite and lubricant was measured by an instrument Roller Air Analyzer or Roller "Particle size Analyzer from Arninco. The:: instrument is an air classi-fier, which separates materi.al by diameter and density..
$0 grans of sample was used. The fraction of bonded graphite is calculated by comparing the content of graph-ite before and after the air classification. Bonding in this case is expressed as I bonded graphite.

Mixtures including iron powder, 0.5% by weight of graph-ite and 0.8% by weight of a binding/lubricating combina-tion of polyethylene wax with different weight average 5 molecular weight and ethylene bisstearamide, according to table 1, and 0,05% of stearic acid were thoroughly heated and mixed at temperature above the melting point of the polyethylene wax but below the melting point of the eth-ylene bisstearamide. The mixtures were then allowed to 10 cool in order to obtain a bonded powder mixture wherein the graphite particles were bonded to the iron particles.
During cooling 0.06% of an inorganic particulate flow agent was added. Powder properties such as flow, apparent density and dusting were measured. In order to measure the lubricating properties rings with outer diameter of 55 mm, inner diameter of 45 mm and a height of 10 mm were compacted at three different compaction pressures and the energy needed in order to eject the body from the mould after compaction, i. e. ejection energy, were measured.
Table 1 Mixture binding/lubricating combination 1 75% EBS/25% Polywax 400 2 75% EBS/25% Polywax 500 3 75% EBS/25% Polywax 655 4 75% EBS/25% Polywax 750 5 75% EBS/25% Polywax 1000 Mixtures including iron powder, 0.5% by weight of graph-ite and 0.8% by weight of a binding/lubricating combina-tion of polyethylene wax and ethylene bisstearamide in different proportions, and 0,05% of stearic acid, accor-ding to table 2, were thoroughly heated and mixed at tem-perature above the melting point of the polyethylene wax but below the melting point of the ethylene bissteara-mide. The mixtures were then allowed to cool in order to obtain a bonded powder mixture wherein the graphite par-ticles were bonded to the iron particles. During cooling 0.06% of an inorganic particulate flow agent was added.
Powder properties such as flow, apparent density and dusting were measured. In order to measure the lubrica-ting properties rings with outer diameter of 55 mm, inner diameter of 45 mm and a height of 10 mm were compacted at three different compaction pressures and the energy needed in order to eject the body from the mould after compaction, i.e. ejection energy, were measured.
Table 2 Mixture binding/lubricating combination 6 90% EBS/10% Polywax 655 7 75% EBS/25% Polywax 655 8 60% EBS/40% Polywax 655 9 40% EBS/60% Polywax 655 10 100% Polywax 655 Two mixtures including iron powder, 0.5% by weight of graphite and 0.8% by weight of ethylene bisstearamide but with no polyethylene wax were prepared. Mixture no 11 in-cluding 0.05% by weight of stearic acid was thoroughly heated and mixed at temperature above the melting point of the ethylene bisstearamide. The mixture was then al-lowed to cool in order to obtain a bonded powder mixture wherein the graphite particles were bonded to the iron particles. During cooling 0.06% of an inorganic particu-late flow agent was added. Mixture no 12 were thoroughly mixed without heating. Powder properties such as flow, apparent density and dusting were measured. In order to measure the lubricating properties rings with outer dia-meter of 55 mm, inner diameter of 45 mm and a height of mm were compacted at three different compaction pres-sures and the energy needed in order to eject the body from the mould after compaction, i.e. ejection energy, were measured.
10 As can be seen from table 4 best combination of AD, flow, bonding and lubrication properties for the powder metal-lurgical composition containing a binding/lubricating combination including the polyethylene wax and ethylene bis stearamide is achieved when the mean molecular weight of the polyethylene wax is between 500 and 750, the con-tent of polyethylene wax is between 10-90% and the con-tent of ethylene bis stearamide is between 90 and 10% in the binding/lubricating combination.

As can be seen from the following table 4 best combina-tion of AD, flow, bonding and lubrication properties for the powder metallurgical composition containing the bind-ing/lubricating combination including polyethylene wax and ethylene bis stearamide is achieved when the mean mo-lecular weight of the polyethylene wax is between 500 and 750, the content of polyethylene wax is between 20-80%
and the content of ethylene bis stearamide is between 80 and 20% of the binding/lubricating combination.
Table 4 Mixture AD Flow Dust no Bonding g/cm3 sek mg/m3 %
1 3.03 27.5 26 97.8 2 3.09 26.5 23 97.0 3 3.13 24.3 46 100.0 4 3.13 24.8 67 98.6 3.17 24.3 36 100.0 6 3.07 24.7 112 97.3 7 3.13 24.3 46 100.0 8 3.16 24.1 29 99.2 9 3.23 22.9 22 100.0 2.92 25.8 31 100 11 3.28 24.4 39 99.8 12 2.98 33.5 288 54.9 Table 4 Mixture GD GD GD
no 400 MPa 600 MPa 800 MPa g/cm3 g/cm3 g/cm3 1 6.75 7.10 7.23 2 6.74 7.09 7.22 3 6.70 7.06 7.20 4 6.70 7.05 7.19 6.69 7.04 7.19 6 6.69 7.04 7.19 7 6.70 7.06 7.20 8 6.69 7.06 7.20 9 6.67 7.04 7.18 6.69 7.03 7.16 11 6.63 7.00 7.17 12 6.66 7.04 7.18 Table 4 Ejection Ejection Ejection Mixture Energy Energy Energy no 400 MPa 600 MPa 800 MPa J /cm2 J /cm2 J /cm2 1 20.0 28.9 31.4 2 19.8 29.2 31.5 3 20.1 25.9 32.4 4 20.1 30.1 32.5 5 20.1 30.5 34.0 6 20.1 30.6 33.2 7 20.1 25.9 32.4 8 19.4 29.3 33.3 9 18.9 27.3 31.5 10 23.6 31.0 34.9 11 20.1 31.6 38.7 12 19.3 29.0 33.5

Claims (11)

CLAIMS:
1. An improved segregation-resistant and dust-resistant metallurgical composition for making compacted parts, comprising:

(a) at least about 80 percent by weight of an iron or iron-based powder;

(b) at least one alloying powder; and (c) about 0.05 to about 2 percent by weight of a binding/lubricating combination of polyethylene wax and ethylene bis-stearamide, the polyethylene wax having a weight average molecular weight below about 1000 and a melting point below that of ethylene bis-stearamide, and being present in an amount between 10 and 90% by weight of the binding/lubricating combination, wherein the particles of the iron or iron-based powder are coated with a layer of the polyethylene wax binding particles of the alloying element(s) and particles of the ethylene bis-stearamide.
2. Composition according to claim 1, wherein the polyethylene wax has a weight average molecular weight between 400 and 800.
3. Composition according to claim 1 or 2, wherein the binding/lubricating combination is made up by 20-70% by weight of the polyethylene wax and 80-30% by weight of the ethylene bis-stearamide.
4. Composition according to any one of the claims 1-3, wherein the binding/lubricating combination is present in an amount of 0.5-1.5% by weight of the total composition.
5. Composition according to any one of the claims 1-4, further comprising a fatty acid in an amount of 0.005-0.15% by weight of the composition.
6. Composition according to claim 5, wherein the fatty acid is stearic acid.
7. Composition according to any one of the claims 1-6, further comprising a flow agent in an amount of 0.01-1 percent by weight of the total composition.
8. Composition according to any one of the claims 1-7, wherein the flow agent is silicon dioxide.
9. Method of preparing an improved segregation-resistant and dust-resistant metallurgical composition containing alloying powder bound to iron-based powder comprising the steps of - mixing and heating an iron or iron-based powder, an alloying element powder, ethylene bis-stearamide and a pulverulent polyethylene wax and optionally a fatty acid to a temperature above the melting point of the polyethylene wax and below the melting point of the ethylene bis-stearamide - cooling the obtained mixture to a temperature below the melting point of the polyethylene wax for a period of time sufficient to solidify the polyethylene wax and bind the particles of the alloying element to the iron-containing particles in order to form aggregate particles, and optionally - mixing a pulverulent flow agent having a particle size below 200 nanometers, with the obtained mixture in an amount between 0.005 to about 2% by weight of the composition.
10. Method according to claim 9, wherein the flow agent has a particle size below 40 nanometers.
11. Method according to claim 9 or 10, wherein the mixture is heated to a temperature between 70 and 150°C for a period of between 1 and 60 minutes.
CA2550597A 2003-12-22 2004-12-17 Iron-based powder composition comprising a combination of binder-lubricants and preparation of the powder composition Active CA2550597C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
SE0303453A SE0303453D0 (en) 2003-12-22 2003-12-22 Metal powder composition and preparation thereof
SE0303453-5 2003-12-22
PCT/SE2004/001905 WO2005061157A1 (en) 2003-12-22 2004-12-17 Iron-based powder composition comprising a combination of binder-lubricants and preparation of the powder composition

Publications (2)

Publication Number Publication Date
CA2550597A1 CA2550597A1 (en) 2005-07-07
CA2550597C true CA2550597C (en) 2011-02-08

Family

ID=30768772

Family Applications (1)

Application Number Title Priority Date Filing Date
CA2550597A Active CA2550597C (en) 2003-12-22 2004-12-17 Iron-based powder composition comprising a combination of binder-lubricants and preparation of the powder composition

Country Status (19)

Country Link
US (1) US7255724B2 (en)
EP (1) EP1697072B1 (en)
JP (2) JP5095219B2 (en)
KR (1) KR100808333B1 (en)
CN (1) CN100475388C (en)
AT (1) ATE446815T1 (en)
AU (1) AU2004305411B2 (en)
BR (1) BRPI0418018B1 (en)
CA (1) CA2550597C (en)
DE (1) DE602004023877D1 (en)
ES (1) ES2335413T3 (en)
MX (1) MXPA06007206A (en)
PL (1) PL1697072T3 (en)
RU (1) RU2314896C1 (en)
SE (1) SE0303453D0 (en)
TW (1) TWI331632B (en)
UA (1) UA79412C2 (en)
WO (1) WO2005061157A1 (en)
ZA (1) ZA200604404B (en)

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7341619B2 (en) * 2004-11-23 2008-03-11 Chevron Phillips Chemical Company, Lp Olefin waxes having improved hardness or viscosity
US7527686B2 (en) * 2004-11-23 2009-05-05 Chevron Phillips Chemical Company, Lp Olefin waxes having improved hardness or viscosity
PL1968761T3 (en) 2005-12-30 2013-08-30 Hoeganaes Ab Metallurgical powder composition
CA2699033C (en) 2007-09-14 2013-05-28 Jfe Steel Corporation Iron-based powder for powder metallurgy
EP2221130B1 (en) * 2007-12-13 2019-04-24 JFE Steel Corporation Iron based powder for powder metallurgy and manufacture thereof
US20090156714A1 (en) * 2007-12-17 2009-06-18 Subramaniam Narayan Flame retardant compositions
ES2620444T3 (en) 2008-11-26 2017-06-28 Höganäs Ab (Publ) Lubricant for powder metallurgical compositions
EP2475481B1 (en) * 2009-09-08 2014-06-18 Höganäs AB Metal powder composition
CN102666895B (en) * 2009-10-26 2015-01-07 霍加纳斯股份有限公司 Iron based powder composition
CN105228774A (en) * 2013-03-14 2016-01-06 赫格纳斯公司 The solvent-free adhesive method of metallurgical composites
US10030209B2 (en) * 2013-09-12 2018-07-24 National Research Council Of Canada Lubricant for powder metallurgy and metal powder compositions containing said lubricant
CN105176636A (en) * 2014-01-14 2015-12-23 莱芜市冠隆纳米科技有限公司 Super lubricant and preparation method thereof
GB201409250D0 (en) * 2014-05-23 2014-07-09 H Gan S Ab Publ New product
US20190084039A1 (en) * 2016-03-18 2019-03-21 Hoganas Ab (Publ) Powder metal composition for easy machining
JP7077117B2 (en) * 2018-04-25 2022-05-30 株式会社神戸製鋼所 Manufacturing method of mixed powder for powder metallurgy
RU2701232C1 (en) * 2018-12-12 2019-09-25 Публичное акционерное общество "Северсталь" Method of producing alloyed powder mixture for production of critical structural powder parts
CN112276073B (en) * 2020-09-23 2022-12-30 山东鲁银新材料科技有限公司 Powder metallurgy composition comprising silicon dioxide as a leavening agent and a flow rate enhancer
WO2023187550A1 (en) * 2022-03-29 2023-10-05 Tata Steel Limited A method of coating iron powder particles with nano silica particles

Family Cites Families (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE427434B (en) 1980-03-06 1983-04-11 Hoeganaes Ab IRON-BASED POWDER MIXED WITH ADDITION TO MIXTURE AND / OR DAMAGE
SE438275B (en) 1983-09-09 1985-04-15 Hoeganaes Ab MIX-FREE IRON-BASED POWDER MIX
GB8502148D0 (en) * 1985-01-29 1985-02-27 Alcan Int Ltd Metal-forming lubricant
US4834800A (en) 1986-10-15 1989-05-30 Hoeganaes Corporation Iron-based powder mixtures
SE468121B (en) 1991-04-18 1992-11-09 Hoeganaes Ab POWDER MIXING CONTAINING BASIC METAL POWDER AND DIAMID WAX BINDING AND MAKING THE MIXTURE
US5298055A (en) 1992-03-09 1994-03-29 Hoeganaes Corporation Iron-based powder mixtures containing binder-lubricant
US5290336A (en) 1992-05-04 1994-03-01 Hoeganaes Corporation Iron-based powder compositions containing novel binder/lubricants
US5368630A (en) 1993-04-13 1994-11-29 Hoeganaes Corporation Metal powder compositions containing binding agents for elevated temperature compaction
US5782954A (en) * 1995-06-07 1998-07-21 Hoeganaes Corporation Iron-based metallurgical compositions containing flow agents and methods for using same
US5840469A (en) * 1997-05-13 1998-11-24 Imation Corp. Gallic acid as a laser direct thermal developer
SE9703151D0 (en) * 1997-09-01 1997-09-01 Hoeganaes Ab Lubricant for metallurgical powder compositions
US6280683B1 (en) 1997-10-21 2001-08-28 Hoeganaes Corporation Metallurgical compositions containing binding agent/lubricant and process for preparing same
CA2307109C (en) * 1997-10-21 2009-09-08 Hoeganaes Corporation Improved metallurgical compositions containing binding agent/lubricant and process for preparing same
JP4228547B2 (en) * 2000-03-28 2009-02-25 Jfeスチール株式会社 Lubricant for mold lubrication and method for producing high-density iron-based powder compact
US6534564B2 (en) * 2000-05-31 2003-03-18 Hoeganaes Corporation Method of making metal-based compacted components and metal-based powder compositions suitable for cold compaction
JP2002020801A (en) * 2000-07-07 2002-01-23 Kawasaki Steel Corp Iron-based powdery mixture for powder metallurgy
US6464751B2 (en) 2000-10-06 2002-10-15 Kawasaki Steel Corporation Iron-based powders for powder metallurgy
SE0103398D0 (en) * 2001-10-12 2001-10-12 Hoeganaes Ab Lubricant powder for powder metallurgy

Also Published As

Publication number Publication date
DE602004023877D1 (en) 2009-12-10
ES2335413T3 (en) 2010-03-26
CA2550597A1 (en) 2005-07-07
JP5271958B2 (en) 2013-08-21
AU2004305411B2 (en) 2008-03-06
US7255724B2 (en) 2007-08-14
BRPI0418018A (en) 2007-04-17
BRPI0418018B1 (en) 2013-10-22
PL1697072T3 (en) 2010-03-31
CN100475388C (en) 2009-04-08
CN1898050A (en) 2007-01-17
ZA200604404B (en) 2007-10-31
TW200533760A (en) 2005-10-16
TWI331632B (en) 2010-10-11
JP2007517980A (en) 2007-07-05
JP2010168667A (en) 2010-08-05
MXPA06007206A (en) 2006-08-18
RU2314896C1 (en) 2008-01-20
KR20060126733A (en) 2006-12-08
US20050139039A1 (en) 2005-06-30
ATE446815T1 (en) 2009-11-15
AU2004305411A1 (en) 2005-07-07
SE0303453D0 (en) 2003-12-22
JP5095219B2 (en) 2012-12-12
KR100808333B1 (en) 2008-02-27
EP1697072B1 (en) 2009-10-28
UA79412C2 (en) 2007-06-11
WO2005061157A1 (en) 2005-07-07
EP1697072A1 (en) 2006-09-06

Similar Documents

Publication Publication Date Title
CA2550597C (en) Iron-based powder composition comprising a combination of binder-lubricants and preparation of the powder composition
EP1094909B1 (en) Iron-based metallurgical compositions containing flow agents and methods for using same
US7682558B2 (en) Metallurgical powder composition
JP4769806B2 (en) Metallurgical powder composition and parts produced therefrom
CA2474253C (en) Improved powder metallurgy lubricant compositions and methods for using the same
WO2001017717A1 (en) Improved metal-based powder compositions containing silicon carbide as an alloying powder
EP1468585B1 (en) Improved powder metallurgy lubricant compositions and methods for using the same

Legal Events

Date Code Title Description
EEER Examination request